Stoker apparatus



May 2, 1944.-

R. A. FORESM AN STOKER APPARATUS Filed Aug.. 26, 1942 2 SheetsSheet 1 INVENTOR Rosem- H. FBRasMaN.

WITNESSES:

BY 451M ATTORNEY y. 19 4 R. A. F ORESMAN 2,347,819

STOKER APPARATUS Fi led Aug. 26,, 1942 2 Sheets-Sheet 2 V .maanwa In n 5 as ///////J //////A% 3 t" 5 f INVENTOR Rossn'r R F'omss MnN.

ATTORNEY Patented May 2, 1944 UNITED STATES STOKEB'APPARATUS Robert A. Foresnian, Prospect Park, Pa., assignor to Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa, a corporation of Pennsylvania Application August 26, 1942, Serial No. 456,217

15 Claims. o1. 122-41 I bars 2! adapted to have undulatory motion im- This invention relates to. stokers, more particularly to those. of the progressive feed type,

and has for an object to provide improved ap paratus of this character.

Another object of the invention is to provide, in a progressive-feed stoker, a fuel-supporting surface downwardly inclined in the direction of fuel feed and unbroken from top to bottom by steps, ledges, etc., to which clinker formations might adhere.

A further object of the invention is to provide a water-cooled multiple retort stoker whose tuyere rows present a-smooth fuel-supporting surface.

Yet another object of the invention is to provide an improved tuyere construction embodying air distribution passages.

A further object of the invention is to provide a novel tuyre assembly embodying one or more conduits for flow of cooling medium.

These and other objects are effected by my invention as will be apparent from the following description and claims taken in connection with the accompanying drawings, forming a part of this application, in which:

Fig. 1 is a side elevational view, partially in section, with portions thereof broken away for the sake of clearness, and illustrating one embodiment of the present invention;

. Fig. 2; is an enlarged fragmentary view of a stoker tuyere row embodying the invention;

, Fig. 3 is a transverse sectional view taken along the line III-III of Fig. 2, looking in the direction of the arrows;

Fig. 4 is a similar view taken along the line IVIV of Fig. 2, looking in the direction of the arrows;

Fig. 5 is a view similar to Fig. 4 showing the parts thereof in exploded position; and,

Figs. 6 and 7 are transverse sectional views taken along the lines VIVI and VIIVII, respectively, of Fig. 2, looking in the direction of the arrows.

; Referring to the drawings in detail, there is shown a furnace I!) having a frontv wall H through which fuel is fed from the hopper l2 by a ram (not shown) housed within the ram box 13 and operated by the conventional stoker engine M. Fuel fed through the front Wall is advanced from front to rear of the furnace by an underfeed stoker l5, comprising alternatelydisposed retorts I! and tuyere rows !8. The retorts and tuyre rows are followed, in the di rection. of fuel feed, by an overfeed section l9,

comprising a plurality. of pivotally connected. 55' adapted. toclosely embracethe upper portions of parted thereto by'links 22 and crank arm 23, the latter being operated from the stoker engine mechanism. Air under pressure for combustion. purposes is supplied to the plenum chamber 2Q,

A row of longitudinally-aligned lower tuyere members 32 are supported upon the upper edges 2.5 of the side walls 21' and bridge the space 3!, each tuyre member having an opening 33 therethrough for passage of air from the space 3! and the plenum chamber 24. Also, each member 32 has, extending upwardly from its upper sur: face, a centrally-disposed boss 34 and, at each side of the latter, pegs 3t and lugs 31. Arow of longitudinally-aligned upper tuyere members 38 rests upon and is supported by the row of lower tuyre members 32, and the members 38 are provided with downwardly-projecting bosses 39, pegs 4| and lugs 42, adapted to bear upon the corresponding bosses 3d, pegs 538 and lugs 31 of the lower tuyre member 32.

It will be apparent that the assembled upper and lower tuyre members have therebetween tortuous lateral passages between and around the pegs and lugs, providing for flow of air from the plenum chamber'24. and through the opening 33 in the lower tuyere member to the side edges of the assembled tuyres.

The upper tuyre members 38 are provided with longitudinally-extending grooves or channels G3 in their upper surfaces, adapted to closely receive a pair of tubes 44 for passage of cooling medium. While these tubes are supported intermediate their ends by the upper tuyre members 38, their terminal portions are mounted in and carried by upper and lower end castings i6 and M, respectively.

A row of longitudinally-aligned tuyere cap members 43 is disposed in overlyingrelation to the tubes 44 and the upper and lower tuyere members 38 and 32, the cap members having grooves orv channels 49 in their under surface to. 1 H V The various tuyre members are held in assembled relation by suitable means, such as the stud ".15 at 53, and extending through vertical aligned" the tubes 44. Preferably, the tuyre cap members are provided with a convex upper fuel-supporting surface 5!, and the side edges of the upper and lower tuyre members 38 and 32 are shaped to form approximate continuations of the outline of the tuyre cap member, whereby there is provided a tuyre assembly which presents a relatively smooth fuel-supporting surface throughout the length of the tuye row, with the resultthat there islittle or no tendency or opclinker formations to adhere therewith cooling means, it will be apparent to those portunity for 52, threadedly secured in the tuyre cap member,

' lateral displacement of the tuyre assembly with respect to the side walls 21. The tuyere upper end casting 46-is formed in two halves 6B and 6'! for the sake of ease of manufacture, the halves 86 ands! being provided with chambers 68 and 69, respectively, adapted to fluid and the latter returned to the supply header 92 by the pipes 98, 99, I89, IOI and I92.

In order to complete the cooling of the tuyere construction for the entire stoker, the side wall tuyres I94 may have cooling tubes I95 arranged in heat transfer relation thereto, cooling medium being supplied through pipes I96 and H11, and led away by pipes I08 and I09 communicating with the heat exchanger 96.

While in the embodiment herein illustrated, the tuyre assemblyhas been shown as provided skilled in the art that there may be conditions ,or circumstances where the use of the cooling tubes 44 maybe dispensed with, in which case the grooves or channels 43 and 49 in the upper tuyere member 38 and the tuyere cap member 48 may be omitted and the tuyere cap member 48 may communicate with the upper or discharge endsof' the tubes '44. Horizontally-disposed air passages H are provided above the chambers 68 and 69, and have laterally-directed exhaust or tuyre passages I2, the passage H receiving air from the plenum chamberby wayof the space 3| between the tuyere row side walls 21 (Fig. 2). The uppermost portions of the castings 66 and 61 are flattened, as at 1.3, to provide a horizontal supporting surface for the conventional air distribution box structure 14 and are provided at their bottom edges with supporting flanges 16 having depending lugs ,11 at the inner edges thereof, the flanges 76 being adapted to rest-upon the flanges 28 of the tuyre lower side walls, with the depending lugs 11 abutting the inner edges of the flanges 28, whereby lateral displacement of the castings is prevented.

The side walls of the castings are provided with a plurality of air discharge passages 18, I9 and 8| for flow of combustion air from the plenum chamber 24 and space 3I.

In order to better interlock the castings 66 and 61 and to prevent fine fuel from passing downwardly through the joint therebetween, the casting 66 is provided witha laterally projectin g lip 82 adapted to be received in a mating rabbet 83 formed in the casting 61.

The lower hollow end casting 4! is of a construction very similar to that just described for the upper end casting except that the flattened upper surface 53 and the air passages II and 12 are lacking. The two halves 84 and 89 have chambers 81 and 88,'respectively, communicating with the tubes 44 and with supply passages 89 which, together with the pipes 9|, conduct cooling fluid from the horizontal header 92. Cooling medium thus supplied to the tubes 44 discharges from the latter through the upper end casting 46 and then, by way of pipes 93, 94 and 95, is conducted to the heat exchanger 96 where theheat takenfrom the tuyre assembly by the fluid pass-v ing through the tubes 44 is removedfrom such,

be formed integral with the upper tuyre member 38, if desired.

While the invention has been shown in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof, and it is desired, therefore, that only such limitations shall be placed thereupon as are specifically set forth in the appended claims.

What is claimed is:

1. A furnace stoker comprising alternately-disposed retorts and tuyre rows, each of said tuyre rows comprising a pair of spaced side walls and a tuyre assembly bridging the space therebetween; said tuyre assembly comprising a plurality of lower tuyere members having openings therethrough for passage .of air from the space between the side walls; said members extending from one side wall to the other and being supported thereby; a plurality of upper tuyre members carried by the lower tuyere members; said upper and lower members providing therebetween passages for flow of air laterally from the openings through the lower tuyere members; and a plurality of tuyre cap members overlying said upper tuyere members and providing a smooth upper fuel-supporting surface for each tuyre assembly,

2. Structure as specified in claim 1, including means for liquid cooling said tuyere assembly,

3. Structure as specified in claim 1, including a tube for conducting cooling fluid disposed longitudinally of each tuyre row in heat transfer relation to the tuyere assembly and protected by the tuyere cap members from exposure to fuel burning in the furnace.

4. Structure as specified in claim 1, including a tube for conductingcoolin fluid extending longitudinally of each tuyre row between the upper tuyre members and the tuyrecap members in heat transfer relation thereto.

5. Structure as specified in claim 1, including a pair of cooling fluid tubes extending longitudinally of each tuyere row in side-by-side relation, and meansfor clamping said tubes between the upper tuyre members and the tuyere cap members, whereby said tubes are protected by the tuyre cap members from burning.

6. In an underfeed stoker, a plurality of spaced retorts having side walls, the adjacent side walls ofadjoining retorts being spaced apart to provide air spaces; a plurality of lower tuyre members supported by said adjacent side walls and bridging the air spaces therebetween, said members having openings therethrough for flow of air from said air spaces; a plurality of upper tuyre mem.

bers assembled on the lower tuyere members, said upper and lower members providing therebetween lateral passages communicating at their inner ends with said openings for receiving air from the air spaces and discharging at their outer ends at the lateral edges of the assembled tuyre members; and a plurality of tuyere cap members over.- lying the assembled upper and lower tuyere members and providing a smooth fuel-supporting surface. 7. Structure as specified in claim 6, including lugs extending into the lateral passages and rendering the latter tortuous. 8. Structure as specified in claim 6, including upwardly-projecting pegs on the lower tuyer'e members and downwardly-projecting pegs on the upper tuyre members, said pegs being adapted, when the tuyere members are assembled, to extend into the lateral passages and render the latter tortuous.

9. Structure as specified in claim 6, including means for liquid-cooling the tuyre members.

10. In an underfeed sto-ker, a plurality of spaced retorts having side walls, the adjacent side walls of adjoining retorts being spaced apart to provide tuyre members and extending longitudinally in substantially parallel relation to the upper edges of the retort side walls; and tuyre cap members overlying the conduits and providing fuel-supporting surfaces thereabove.

11. Structure as specified in claim 10, including means for retaining the upper tuyere members and the tuyre cap members in heat transfer relation to the conduits.

12. Structure as specified in claim 10, wherein each row of tuyere members has a pair of parallel conduits associated therewith.

13. Structure as specified in claim 10, including means for retaining the tuyre lower and upper members, the tuyere cap members and the conduits in assembled relation as composite units.

14. Structure as specified in claim 10, including means for retaining the tuyre upper, lower and cap members and the conduits in assembled relation as composite units and for preventing lateral displacement of said units with respect to their supporting retort side walls.

15. IA furnace stoker comprising alternatelydisposed retorts and tuyere rows, each of said tuyere rows comprising a pair of spaced side walls whose upper edges are inclined downwardly from the front of the furnace towards the rear and a tuyere assembly bridging the space between said side walls; said tuyre assembly comprising a row of lower tuyre members having vertical openings for passage of air therethrough from the space between the side walls; said lower tuyre members resting on the inclined side wall upper edges in longitudinal alignment and bridging the space between said walls; a row of upper tuyere members supported by said lower tuyr members; said upper and lower tuyere members providing therebetween lateral passages for flow of air from the vertical openings of the lower tuyre members; and a row of longitudinally-aligned tuyere cap members overlying the upper tuyere members and having convex upper surfaces providing a downwardly-inclined, fuel-supporting surface which is smooth from top to bottom, whereby free fuel-bed movement thereover may occur.

ROBERT A. FORESMAN. 

